The invention relates to communication devices and methods of use thereof in ad hoc networks that operate with reduced energy consumption.BACKGROUND Ad hoc networks include a plurality of nodes, many of which are mobile, in wireless communication with one another. The topology of ad hoc networks varies as the nodes move with respect to each other, coming in and out of range of each others'transmitters. Typically, nodes in ad hoc networks schedule their communications with each other using various time division and/or frequency division multiplexing schemes. In practice, a communication device using a periodic TDMA communications protocol remains in one of two states, transmit or receive. To remain in either state, the communication device supplies power to a transceiver. For many communicationdevices, the device is predominantly idle, waiting in a powered receive state in case an incoming message arrives. A deficiency of this approach is that in low network traffic environments, the amount of energy used in an idle receive state dominatesthe total energy used by the communication device.SUMMARY The invention addresses the deficiencies in the prior art by providing, in various aspects, systems, methods, and devices relating to limiting the time that the communication devices spend in a powered receive state. According to oneembodiment, a first communication device includes at least one transceiver and a communications control processor. The communications control processor receives scheduling data from a second communication device. The scheduling data enables the firstcommunication to predict a time at which the second communication device will be available to receive communications. The communications control processor causes the transceiver to transmit a communication to the second communication device at thepredicted time. According to another embodiment, the second communication device also includes at least one transceiver and a communications control